XYNCoder is an all audio/video formats to MP4 batch encoding frontend.It can convert any audio or video file, that can be played back by MPlayer, to MP4.It uses the x264(mencoder) for video and aac(neroaacenc) for audio encoding. It can use AviSynth(optionally) to perform any preprocessing on the source. Also it can be used as a standalone encoding frontend for NeroAacEnc.Video(Mencoder) encoding settings:XYNCoder can encode using 4 different modes: * 1 pass crf mode * 1 pass bitrate mode * 2 pass bitrate mode * 2 pass optimal quality mode (default) The last mode is the reason why this tool was written in the first place. This mode can be used for 2 pass encodes where the target size is not as important as the final video quality. It produces high quality 2 pass encodes with a single click.This is how it achieves that: * perform the first pass encode with a crf set to 16 * perform the second pass with the target bitrate set to half of the first pass bitrate This method invariably produces high quality 2 pass encodes with often surprisingly small file sizes. Most of the advanced encoding settings are hidden from the user and have been preset to provide high quality encodes. The only setting exposed is the deblock filter strength, which provides pretty good results at the default of 0,0.The user can also specify the usage of AviSynth here and then edit the script to suit his needs.The 1 pass crf(constant ratefactor) mode is to x264 what other codecs refer to as the constant quality mode. The recommended values of crf are in the ranges of 18-28, with lower numbers producing better quality/higher filesizes.The remaining two modes use the bitrate as a guiding factor.